A dark pattern (or deceptive pattern) is an interface designed to push users into making choices they wouldn't have made otherwise: subscribing, sharing, paying, or accepting.

The term was coined in 2010 by designer Harry Brignull, who has curated the catalog (deceptive.design) ever since. In it, we recognize tactics that have become all too familiar: confirmshaming ("No thanks, I prefer paying full price"), the roach motel (easy to sign up, incredibly hard to cancel), hidden costs revealed only on the final checkout screen, and consent extracted through a deliberately unbalanced interface.

These are not accidents. A dark pattern is the product of a conflict of interest: what serves the business (conversion, retention, data collection) is not what serves the user. When we optimize an interface solely for conversion, design mechanically slips from helpful guidance to outright coercion – often without anyone explicitly deciding to do so.

It is the exact same mechanism as affordance, just turned upside down. Guidance puts form at the service of the user's intent; manipulation puts it at the service of another intent entirely, by exploiting cognitive bias and attention fatigue. The boundary isn't a technical one; it lies in the answer to one simple question: who wins when the user clicks?

Naturally, the law has stepped in. The GDPR regulates "free and informed" consent; the European Digital Services Act (2022) explicitly bans dark patterns on major platforms; and several regulators, including France's CNIL and the US FTC, now penalize deceptive designs. The signal is crystal clear: interface manipulation is no longer a free ride.

Our philosophy: the true performance of a design is not measured by what it forces people to click, but by the conscious decisions it empowers them to make. A service that traps its users wins a quick conversion but loses the relationship. Designing with integrity is not just an ethical requirement – it is a powerful trust building strategy, and therefore, a winning strategy for the long term.

What is at play elsewhere: affordance (the same grammar, done right), attention and cognitive bias (what dark patterns exploit), acceptability (the user's limit), design ethics, and trust.

References: H. Brignull, deceptive patterns (2010); European Digital Services Act Regulation (2022); GDPR, consent requirements.